Convert to Subtask
Group your subtasks under the parent task regardless of which one you created first with a few clicks.
Transcript
How to use
Method 1
Open the task details.
Click on the 3 dots menu.
Click "Convert to subtask".
Select the parent task and confirm.
Done.
Method 2
Open Table View.
Right click on the task you want to convert.
Click "Convert to subtask".
Select the parent task and confirm.
Done.
Note
You can convert subtasks to tasks in the exact same way.